@Article{info:doi/10.2196/65879,
author="Bennetot, Adrien
and Zia Ur Rehman, Rana
and Romijnders, Robbin
and Li, Zhi
and Macrae, Victoria
and Davies, Kristen
and Ng, Wan-Fai
and Maetzler, Walter
and Kudelka, Jennifer
and Hildesheim, Hanna
and Emmert, Kirsten
and Paulides, Emma
and van der Woude, C Janneke
and Reilmann, Ralf
and Aufenberg, Svenja
and Chatterjee, Meenakshi
and Manyakov, Nikolay V
and Pinaud, Cl{\'e}mence
and Avey, Stefan",
title="Characterizing Patient-Reported Fatigue Using Electronic Diaries in Neurodegenerative and Immune-Mediated Inflammatory Diseases: Observational Study",
journal="JMIR Form Res",
year="2025",
month="May",
day="5",
volume="9",
pages="e65879",
keywords="chronic disease; fatigue; neurodegenerative diseases; immune-mediated inflammatory diseases; diary, patient-reported outcomes; electronic diaries; digital technologies; digital health; eHealth; mobile phone",
abstract="Background: Fatigue is a prevalent and debilitating symptom in many chronic conditions, including immune-mediated inflammatory diseases (IMIDs) and neurodegenerative diseases (NDDs). Fatigue often fluctuates significantly within and between days, yet traditional patient-reported outcomes (PROs) typically rely on recall periods of a week or more, potentially missing these short-term variations. The development of digital tools, such as electronic diaries (eDiaries), offers a unique opportunity to collect granular, real-time data. However, the feasibility, adherence, and comparability of eDiary-based assessments to established PROs require further investigation. Objective: This study aimed to evaluate the feasibility and acceptability of using a high-frequency eDiary to capture intraday variability in fatigue and to compare eDiary data with scores obtained from the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), a validated weekly recall PRO. Methods: Data were collected from 159 participants enrolled in the IDEA-FAST (Identifying Digital Endpoints to Assess Fatigue, Sleep and Activities in Daily Living in Neurodegenerative Disorders and Immune-Mediated Inflammatory Diseases) feasibility study; a 4-week prospective observational study conducted at 4 European centers. Participants included individuals with NDDs (n=39), IMIDs (n=78), and healthy volunteers (n=42). Participants used an eDiary to report their physical and mental fatigue levels up to 4 times daily on a 7-point Likert scale (0=low and 6=high). Adherence was calculated as the proportion of completed eDiary entries relative to the total expected entries. Correlations between averaged eDiary scores and weekly FACIT-F scores were analyzed. Results: Adherence to the eDiary protocol was 5505/8880 (61.99{\%}) overall, varying by cohort, with the highest adherence (1117/1200, 93.07{\%}) observed in the primary Sj{\"o}gren syndrome cohort and the lowest adherence in the Parkinson disease (410/960, 42.7{\%}) and Huntington disease (320/720, 44.4{\%}) cohorts. The average adherence was 430/1680 (43.45{\%}) in the NDD cohorts and 3367/4560 (73.84{\%}) in the IMID cohorts. Fatigue levels showed clear diurnal variation, with significantly higher fatigue reported in the evening compared to the morning (P<.001). A moderate correlation (Spearman=0.46, P<.001) was observed between eDiary fatigue scores and FACIT-F scores, with stronger cohort-specific associations for certain FACIT-F items. These results indicate that eDiaries provide complementary insights to weekly PROs by capturing intraday fluctuations in fatigue. Conclusions: This study demonstrates the feasibility, acceptability, and validity of using high-frequency eDiaries to assess fatigue in chronic conditions. By effectively detecting intra- and interday fatigue variations, eDiaries complement traditional PROs such as FACIT-F, offering a more nuanced understanding of fatigue patterns. Future research should explore optimized eDiary protocols to balance participant burden with data granularity. ",
issn="2561-326X",
doi="10.2196/65879",
url="https://formative.jmir.org/2025/1/e65879",
url="https://doi.org/10.2196/65879"
}